DHAKA: The personal data of four million customers may have been stolen in a "significant and sustained cyberattack" targeting one of Britain's leading phone providers.

U.K. telecom TalkTalk has admitted that its website was hacked earlier this week, and that information including the date of birth, address, credit card and bank details of its four million customers is at risk, reports the CNN.

Police have launched a criminal investigation into the attack, but no arrests have been made. The scale of the breach is still being investigated, police said.

"We take any threat to the security of our customers' data extremely seriously and we are taking all the necessary steps to understand what has happened here," TalkTalk CEO Dido Harding said in a statement.

BDST: 1624 HRS, OCT 23, 2015
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